in how many ways can 2mango, 3 black berry and 3 tamarind trees can be planted in a straight line. if one does not distinguish between trees of the same kind.
9!/(3!3!2!)
n! = total ways that's 9.
3! bc there are 3 similar blackberries, 2! bc there are 2 similar mangoes and another 3! bc there are 3 similar tamarind.
PS "similar" is the key here.
